The placement would be Thousands
Well the answer would be One'th because you dont start at the two and then count your decimal like
21.939 the one is were you start one'th the nine is tenth and the 3 is hundreth and 9 thousanth
The place value of the digit '1' in the number 21.939 is in the ones place, representing a value of 1. It contributes one whole unit to the overall number. The other digits do not change the value of '1' in its position.
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